Objective: The aim of this study was to evaluate the anatomic topography of the circumflex artery (Cx) and left atrial appendage (LAA) and to determine the safety zones for epicardial LAA closure and LAA occlusion procedures. Methods: The left coronary artery was segmented and visualized from 116 computed tomography angiography scans. Four points were located on the Cx portion periappendicularly, starting from the entry point. The landing zone plane was defined as parallel to the LAA orifice at the level of the beginning of the periappendicular course of the Cx, and the plane of the neck bend was located at the end of the LAA neck. A distance smaller than 2 mm was considered a dangerous distance. Results: The distance between the Cx and the LAA landing zone was 4.3 ± 2 mm. The distance between the Cx and the LAA neck bend was 5.1 ± 2.2 mm. The distance between the Cx and the LAA bottom surface was 5.8 ± 2.9 mm. In 38.8% of patients, at least 1 distance between Cx and LAA was smaller than 2 mm in at least 1 dimension. These distances occurred in 30.2% of the LAA landing zone dimensions, 19.8% of LAA neck bend dimensions, and 11.2% of the LAA bottom surface distances. Conclusions: The study showed that most dangerous distances (30.2%) occurred in the LAA landing zone dimension. The data showed that landing zones more distal from the orifice of the LAA are safer in terms of Cx damage. Therefore, LAA closure should always be performed with caution, to avoid iatrogenic complications.

The left atrial appendage (LAA) is well known as a source of cardiac thrombus formation. Despite its clinical importance, the LAA neck is still anatomically poorly defined. Therefore, this study aimed to define the LAA neck and determine its morphometric characteristics. We performed three‐dimensional reconstructions of the heart chambers based on contrast‐enhanced electrocardiography–gated computed tomography scans of 200 patients (47% females, 66.5 ± 13.6 years old). The LAA neck was defined as a truncated cone‐shaped canal bounded proximally by the LAA orifice and distally by the lobe origin and was present in 98.0% of cases. The central axis of the LAA neck was 14.7 ± 2.3 mm. The mean area of the LAA neck walls was 856.6 ± 316.7 mm². The LAA neck can be divided into aortic, arterial (the smallest), venous (the largest), and free surfaces. All areas have a trapezoidal shape with a broader proximal base. There were no statistically significant differences in the morphometric characteristics of the LAA neck between LAA types. Statistically significant differences between the sexes in the main morphometric parameters of the LAA neck were found in the central axis length and the LAA neck wall area. The LAA neck can be evaluated from computed tomography scans and their three‐dimensional reconstructions. The current study provides a complex morphometric analysis of the LAA neck. The precise definition and morphometric details of the LAA neck presented in this study may influence the effectiveness and safety of LAA exclusion procedures.

The pericardial sinuses are an important anatomical feature of the pericardial cavity, however, their clinical anatomy has not been thoroughly studied. In this study, we aim to provide the first classification of the oblique and transverse sinuses. We analyzed 121 computer tomography scans (46.3% female, age of 66 ± 12 years) of the pericardial cavity. The oblique sinuses were classified into four types: 1 (shallow with narrow entrance), 2 (shallow with wide entrance), 3 (deep with narrow entrance), and 4 (deep with wide entrance). The transverse sinuses were classified into four types: Concave, Wine-type, Straight, and Convex. The most common oblique sinus type was Type 1. The median oblique sinus volume was 8.4 (5.3) mL, the median entrance length was 33.0 (13.2) mm, and the depth was 38.2 (11.8) mm. The most common transverse sinus type was Concave. The median transverse sinus volume was 14.8 (6.5) mL, and the median length was 52.8 (17.7) mm. Our study provides an anatomical classification of the pericardial sinuses. The individual variability of the sinuses’ morphology highlights the importance of understanding the clinical topography of the sinuses, particularly for minimally invasive thoracic ablation procedures.

Summary: Patients with preoperative atrial fibrillation (AF) undergoing cardiac surgery face a heightened risk of complications and reduced survival. Concomitant surgical ablation (SA) has shown promise in mitigating the arrhythmic burden, prompting guideline upgrades by major scientific societies. However, SA remains underutilized, with performance rates varying between 22% and 48%, depending on the type of procedure. The goal of this narrative review is to summarize current evidence to aid physicians in decision making regarding AF management during cardiac surgery. This review examines existing literature on the prevalence, management and outcomes of AF in cardiac surgery. We assess epidemiological data, summarize trends in clinical practice and review the rationale and techniques for treating AF surgically. Emerging challenges, including barriers to implementation and novel therapeutic advancements, are also discussed. Evidence underscores the detrimental impact of preoperative AF on perioperative and long-term outcomes, including higher mortality, morbidity and thromboembolic risk. Concomitant SA, particularly the Cox-maze IV procedure, significantly improves sinus rhythm restoration, reduces mortality and mitigates complications like stroke. However, the procedure remains underperformed due to concerns about complexity, prolonged operative time and training gaps. Emerging hybrid techniques, novel mapping systems and technologies like pulsed field ablation may enhance outcomes and broaden SA adoption. Concomitant SA is an effective yet underutilized therapy that can improve survival and reduce AF-related complications in cardiac surgery patients. Addressing implementation barriers and integrating advancements in technology and surgical approaches are key to optimizing patient outcomes.

Background and Objectives: Left atrial appendage closure is an alternative treatment to reduce thromboembolism in patients with atrial fibrillation in whom oral anticoagulation (OAC) is contraindicated. The aim of this study was to evaluate the complications profiles of the LARIAT and AtriClip devices and perform a comparison between them based on the MAUDE (Manufacturer and User Facility Device Experience) database. Materials and Methods: The Manufacturer and User Facility Device Experience database was searched on 15 January 2023. For AtriClip, only reports regarding isolated procedures or procedures associated with minimally invasive ablation were included. Adverse effects and causes of death were defined based on the literature on the topic and the causes described in the reports. In total, 63 patients were included in the LARIAT group and 53 patients were included in the AtriClip group. Results: With the LARIAT device, the most common complication without device problems was pericardial effusion (n = 18, 52.9%), whereas this complication was not observed with AtriClip (p < 0.001). Postoperative bleeding was a second complication that occurred significantly more often in the LARIAT group—in 15 (44.1%) cases versus 1 (2.7%) case with AtriClip (p < 0.001). In addition, significant differences were found in the prevalence of stroke (LARIAT n = 0 vs. AtriClip n = 7, 18.9%, p = 0.012) and thrombus (LARIAT n = 2, 5.9% vs. n = 11, 29.7%, p = 0.013). Conclusions: Each type of left atrial appendage closure procedure is associated with device-specific requirements and complications that, if known, can be avoided.

The proteomic profile of the human cardiac conduction system: the sinoatrial node (SAN) and atrioventricular node (AVN), remains poorly understood. The aim of the current study is to identify proteomic characteristic of the human SAN and AVN in the comparison to working myocardium of the right atrium (RAM) and right ventricle (RVM). The proteomic analysis was performed on 10 autopsied human heart specimens collected from healthy adults. During the data-independent acquisition proteomics analysis 2752 different proteins were identified in all sample sets. In both nodal tissues (compared to working myocardium), the following pathways were upregulated: regulation of Insulin-like Growth Factor transport and uptake by Insulin-like Growth Factor Binding Proteins, post-translational protein phosphorylation, glutathione metabolism, metabolism of carbohydrates, glycolysis and gluconeogenesis. Other common for nodal tissue pathways were these related to immune system and related to extracellular matrix. The pathways related to cardiac muscle contraction were more abundant in RAM and RVM samples. The current study presents extensive comparative analysis of protein abundance in the human SAN and AVN. Few key differences may be found in the nodal proteome in comparison to working cardiomyocytes, including involvement of immune system and upregulated pathways related to extracellular matrix. The SAN exhibits enrichment in the PPAR signaling and pentose phosphate pathways, as well as prostaglandin synthesis and regulatory proteins, compared to the AVN.